'Gold-Standard' data for wind energy comes from this site: Renewables UK The 'Onshore' + 'Offshore' Capacity is 12,119 MW. From the 29,534,391 MWh of 'Energy Produced', the average generational power works out at 3,369 MW, giving a Capacity Factor of 27.8%.
Page 16 of this site: State of the Industry Report 2014 - Deployment states: "...A snapshot of the UK wind industry taken on 30 June 2014 is shown in Table 1...". Page 15 shows 'Wind Energy Performance Totals' - 'UK-wide Operating' as 11,183 MW.
It is very reasonable to apply the 27.8% Capacity Factor to this 'Total' to give generational power of 3,109 MW, working out at 27,252,389 MWh (27.252 TWh) of 'Energy Produced'.
From this: Renewables UK there are a total of 6,036 Onshore and Offshore turbines, meaning each one has a 2 MW capacity to give the 12,119 MW figure. So, the 30 June 11,183 MW means 5,591 x 2 MW turbines.
5,591 wind turbines generate 3,109 MW - so -
each one is generating 556.07 kW
That's enough to boil 186 Kettles!